Multiscaling of Turbulent Structure Functions

Structure functions measured in a turbulent-wind-tunnel boundary layer are interpreted in terms of the multifractal model. We emphasize that this geometric model has two experimentally verifiable consequences for structure functions: they should exhibit multiscaling and should be subject to a bound on the largest accessible exponent. The experimental results are consistent with multiscaling. To further explore this aspect of the multifractal model, we also performed experiments with very small (100 μm length) probes. The results show that in multifractal turbulence the smallest scales are probably not smaller than the Kolmogorov scale.